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Methods for Pseudo Invariants. Decoupled Damped Systems. Restore “Determinant=1” by scaling the transfer map by the damping factor where D is the determinant of the linear map of the decoupled damped system. Coupled Systems.
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Methods for Pseudo Invariants Decoupled Damped Systems • Restore “Determinant=1” by scaling the transfer map by the damping factor where D is the determinant of the linear map of the decoupled damped system. Coupled Systems • First, decouple the system to 2 x 2 blocks by taking real and imaginary parts of eigen vectors. The Normal Form method can be used for analysis of nonlinear behavior. M. Berz Emittance Exchange Workshop at LBNL, October 3-19, 2001
Tracking a Decoupled Damped System- Quadrupole Cooling Cells - Tracking via the damped transfer map Tracking via the determinant 1 restored transfer map of the damped system M. Berz Emittance Exchange Workshop at LBNL, October 3-19, 2001
Normal Form Theory Goal: perform a nonlinear change of variables such that the motion in the new variable pairs is rotationally invariant: If the map is symplectic, this means circles. If the map is damped, we obtain logarithmic spirals. Advantage: Tune with amplitude is trivial to compute, since each iteration of the map corresponds to the same angle advance. Other Advantages: - Provides pseudo invariants the quality of which allows conclusions about the map; - sensitive to resonances, allows efficient study of resonances. M. Berz Emittance Exchange Workshop at LBNL, October 3-19, 2001
Tracking a Coupled Non-Damped System- sFOFO 2.75m Cells from Study II - Tracking in Regular (x-x’) Coordinates 1-20 Cells 101-120 Cells Tracking in Normal Form Coordinates 1-300 Cells M. Berz Emittance Exchange Workshop at LBNL, October 3-19, 2001
Tracking a Coupled Damped System- sFOFO 2.75m Cooling Cells from Study II - Tracking in Regular (x-x’) Coordinates 1-20 Cells 101-120 Cells Tracking in Normal Form Coordinates 1-300 Cells 41-60 Cells M. Berz Emittance Exchange Workshop at LBNL, October 3-19, 2001